Surpac Tip - TCL/SCL macro series (7 of 10)
Part 7 – Working with TCL lists
SCL provides many excellent functions to create, add, import and manipulate layers and data. There is also great reference material in the Surpac->Help menu. My aim in this series is to introduce some of these features in more layman’s terms. Some knowledge of how macro’s work with variables and commands will certainly be helpful but is not essential.
In the following tip;
- My comments in the code blocks will have a # in front of them. They are also in bold and italicized.
If you would like to test this code in Surpac, the entire code block (Including previous parts 1, 2, 3, 4, 5 and 6) has been added to the end of the tip. Copy it into any text editor and save it with a .tcl extension to use it in Surpac. The final result will be output to the message window and should look similar to below.
Use the puts command to write to the message window.
puts "" puts "Part 7 - TCL lists for storing information"
We have used lists a number of times in this series. Today we'll explore TCL lists in more detail. Previously we have suggested that TCL lists can be thought of exactly like a shopping list where you number each of the items you are going to buy starting with the number 1. The items in our TCL list however, are numbered starting from 0. The list number is known as the "index" number and is an important concept to grasp.
We can add items to a list in a number of ways. First, it is good practice to set up an empty list. In this example the list name is shoppingList.
#Setup an empty list called shoppingList
set shoppingList {}We can then use the "lappend" command to add items into our "shoppingList". Bacon is the first item added and will be stored at index position zero. Cheese is last and will be stored at index position seven.
#Add items to our list with the lappend command lappend shoppingList bacon lappend shoppingList eggs lappend shoppingList bread lappend shoppingList meat lappend shoppingList tomatoes lappend shoppingList potatoes lappend shoppingList onion lappend shoppingList cheese
Internally, TCL looks at your list like below;
list name, index, value
shoppingList, 0, bacon
shoppingList, 1, eggs
shoppingList, 2, bread
shoppingList, 3, meat
shoppingList, 4, tomatoes
shoppingList, 5, potatoes
shoppingList, 6, onion
shoppingList, 7, cheese
The index becomes very important when we want to recall items from our list. We will usually store the value of the recalled item into a variable we can use later. I'll use the set command in front of the lindex command as shown below. This code reads as follows;
Store the value at index position 3 from my shoppingList into a variable called item.
set item [lindex \\\$shoppingList 3]
Write the items value to the message window. In this case "meat" should be written to the message window. Try testing out any value from 0 to 7 in place of the 3 to see the outcome.
#Write to the message window and then add a blank line for readability. puts "Item at index position 3 is \\\$item" puts ""
If I want to see all the items on my list, TCL provides a special looping command to do this. The command is called "foreach" and it allows us to interact with each item in the list separately. There should be 8 items in the list now with the first item stored at index position zero. For clarity, I'm setting a variable called "position" to write the index position of each item to the message window.
Now, how is this working. Firstly, the foreach loop is iterating over the list stored in the variable "\\\$shoppingList". It grabs the first item it sees in the list and stores it in the variable "item". I am then just outputting what the item is to the message window using the "puts" command but in reality, I can do anything I like with this list item. Once the code reaches the final "}" in the foreach loop, it will extract the next "item" in "\\\$shoppingList" until there are no more "items" to grab. TCL then exits the loop and continues with the rest of your code.
#foreach is a special TCL list command designed specifically to iterate over all items in a list, one by one.
set position 0
foreach item \\\$shoppingList {
puts "Item \\\$position is \\\$item"
incr position
}
puts ""You can count how many items are in a list by using the llength command.
#Use the variable "shoppingListLength" to store the number of items in the list set shoppingListLength [llength \\\$shoppingList] puts "There are \\\$shoppingListLength items in your shopping list." puts ""
There are many other commands that can be used with TCL lists. The ones contained here are those that I've found to be most useful when you are just starting out.
Now we've seen basic lists, lets up the complexity a fraction more and look at lists of lists. We use lists of lists to store and gain easy access to more complex, hierarchical data such as points where each point has an x and y value.
puts "Now lets look at lists of lists"
#I have created a list (coordList) and stored four points in it with each point having an x and y value.
set coordList [list {100 100} {100 200} {200 200} {200 100}]In the coordList, each set of {x y} contains an x and y value. The coordList contains 4 points but each point contains 2 values (the x and y coord) This is the hierarchical data structure. We can extract the values from the coordList either by using the index position of the point OR by iterating over all the points using the foreach command. For example, lets grab point 3 (Which is at index position 2)
set point3 [lindex \\\$coordList 2] #point3 is it's own list with the x coord in index 0 and the y coord in index 1 set point3X [lindex \\\$point3 0] set point3Y [lindex \\\$point3 1] puts "Point 3 coords -> X = \\\$point3X, Y = \\\$point3Y" puts ""
Now let's iterate over all points in the coordList
set pointNum 1
foreach point \\\$coordList {
set pointX [lindex \\\$point 0]
set pointY [lindex \\\$point 1]
puts "Point \\\$pointNum coords -> X = \\\$pointX, Y = \\\$pointY"
incr pointNum
}Hopefully you can start to see how this can be utilised in Surpac. In part 8 of this macro series we will continue working with lists to see how easy it is to gather data into a list, sort the data and then write that data back out. The example we'll look at is iterating over blast holes, sorting them by northing and easting, and then writing them to a csv file.
Entire code block - Parts 1 to 7 - Copy into text editor and run in Surpac with .tcl extension
####### PART 1 #######
# Get a reference to the active viewport (You can have more than one) store it in reference variable "vh"
SclGetActiveViewport vh
# Using the "vh" reference, get the active layer and store the reference in the "initialSwa" variable
\\\$vh SclGetActiveLayer initialSwa
# Extract the layer name into the layerName variable using the SCL command "SclGetId"
set layerName [\\\$initialSwa SclGetId]
# Print the layer name to the message window
puts "Layer name is \\\$layerName"
# Create a layer called design that can be manipulated/inquired with the "designSwa" reference variable
SclCreateSwa designSwa "design"
# Use the SclAdd function to add the layer into the layer panel
sclGraphicsLayers SclAdd \\\$designSwa \\\$vh
# Using the reference to "designSwa", create a reference variable "designStr" and make the string number 8
\\\$designSwa SclCreateString designStr 8
# Using the reference to the "designStr" create a reference variable "designSeg" and count how many items (i.e. segments) already
# exist for string 8. If there are 5 existing segments in string number 8, [\\\$designStr SclCountItems] will return a value of 5.
# 5 will become the new segment number. Now, why doesn't this clash with the existing segments if there are already 5 of them?
# This is because the segments are stored as an index position which starts at zero. i.e. segment 1 = index 0, segment 2 = index 1
# ... segment 5 = index 4 and so on.
# All of this to say that when we count how many items are in string 8, the number returned will work as the next index position
# which is what the "SclCreateSegment" function requires. So if I write it manually it becomes
# \\\$designStr SclCreateSegment designSeg 5
\\\$designStr SclCreateSegment designSeg [\\\$designStr SclCountItems]
# Using the reference variable "designSeg" count how many points there are and add this one to the end
\\\$designSeg SclCreatePoint designPnt [\\\$designSeg SclCountItems]
\\\$designPnt SclSetValueByName X 10
\\\$designPnt SclSetValueByName Y 10
\\\$designPnt SclSetValueByName Z 10
\\\$designPnt SclSetValueByName d1 "Testing SCL layer commands"
# Using the reference variable "designSeg" count how many points there are and add this one to the end
\\\$designSeg SclCreatePoint designPnt [\\\$designSeg SclCountItems]
\\\$designPnt SclSetValueByName X 10
\\\$designPnt SclSetValueByName Y 20
\\\$designPnt SclSetValueByName Z 10
# Using the reference variable "designSeg" count how many points there are and add this one to the end
\\\$designSeg SclCreatePoint designPnt [\\\$designSeg SclCountItems]
\\\$designPnt SclSetValueByName X 20
\\\$designPnt SclSetValueByName Y 20
\\\$designPnt SclSetValueByName Z 10
# Using the reference variable "designSeg" count how many points there are and add this one to the end
\\\$designSeg SclCreatePoint designPnt [\\\$designSeg SclCountItems]
\\\$designPnt SclSetValueByName X 20
\\\$designPnt SclSetValueByName Y 10
\\\$designPnt SclSetValueByName Z 10
# To close the shape, make the x,y and z the same as the first point.
\\\$designSeg SclCreatePoint designPnt [\\\$designSeg SclCountItems]
\\\$designPnt SclSetValueByName X 10
\\\$designPnt SclSetValueByName Y 10
\\\$designPnt SclSetValueByName Z 10
# Using the reference to the design layer (designSwa), use the command "SclDraw" to draw everything in the design layer.
\\\$designSwa SclDraw
SclFunction "ZOOM ALL" {}
# Now, the active layer is still the initial layer that was active when the macro was first run. Let's make it the design layer
\\\$vh SclSetActiveLayer \\\$designSwa
####### PART 2 #######
#Create a layer called square_2 that can be manipulated/inquired with the "square2Swa" reference variable
SclCreateSwa square2Swa "square_2"
sclGraphicsLayers SclAdd \\\$square2Swa \\\$vh
# Using the reference to "square2Swa", create a reference variable "square2Str" and make the string number 6
\\\$square2Swa SclCreateString square2Str 6
# Create a new segment. See details from part 1 about how this works.
\\\$square2Str SclCreateSegment square2Seg [\\\$square2Str SclCountItems]
# Procedure is called "newPoint" and takes 4 parameters.
# 1. The segment reference 2. The X coord, 3. The Y coord and 4. the Z coord
proc newPoint {segHandle x y z} {
# The rest of the code is exactly the same as what we did in part one when creating a new point
# The only difference being that we are using variables i.e. \\\$x that are input when the procedure is called.
\\\$segHandle SclCreatePoint pntHandle [\\\$segHandle SclCountItems]
\\\$pntHandle SclSetValueByName X \\\$x
\\\$pntHandle SclSetValueByName Y \\\$y
\\\$pntHandle SclSetValueByName Z \\\$z
return \\\$pntHandle
}
newPoint \\\$square2Seg 11 11 10;# First point, note that we are using square2seg as the segment reference
newPoint \\\$square2Seg 11 19 10
newPoint \\\$square2Seg 19 19 10
newPoint \\\$square2Seg 19 11 10
newPoint \\\$square2Seg 11 11 10;# Closing point is same as first point
# Create a layer called square_3 that can be manipulated/inquired with the "square3Swa" reference variable
SclCreateSwa square3Swa "square_3"
sclGraphicsLayers SclAdd \\\$square3Swa \\\$vh
# Using the reference to "square3Swa", create a reference variable "square3Str" and make the string number 9
\\\$square3Swa SclCreateString square3Str 9
# See details from part 1 about how SclCreateSegment works.
\\\$square3Str SclCreateSegment square3Seg [\\\$square3Str SclCountItems]
newPoint \\\$square3Seg 13 13 10;# First point, note that we are using square3seg as the segment reference
newPoint \\\$square3Seg 13 17 10
newPoint \\\$square3Seg 17 17 10
newPoint \\\$square3Seg 17 13 10
newPoint \\\$square3Seg 13 13 10;# Closing point is same as first point
\\\$square2Str SclDraw
\\\$square3Str SclDraw "style=ssi_method=line,HGS_color=line=red,HGS_line_weight=2"
####### PART 3 #######
puts ""
puts "Part 3 - layer iteration and finding the layer you want. Plus, creating a small GUIDO form."
# Get a handle to the active viewport and store it in reference variable "vh"
SclGetActiveViewport vh
# Use sclGraphicsLayers command with SclIterateFirst command to setup a layer iterator
sclGraphicsLayers SclIterateFirst Iterator
# Using a TCL while loop, keep iterating over the layers until there are no more to iterate over.
while {[\\\$Iterator SclIterateNext SwaHandle] == \\\$SCL_TRUE} {
# Write the layer name to the message window by inquiring the SwaHandle reference variable using the SclGetId command.
puts "Layer name is [\\\$SwaHandle SclGetId]"
# store the layername into a variable called "layerName"
set layerName [\\\$SwaHandle SclGetId]
# Don't store the main graphics layer into the list of selectable layers as it may be empty.
if {\\\$layerName != "main graphics layer"} {
# Append the layerName into a list called layerList. TCL lists are simple. Just imagine a shopping list.
lappend layerList \\\$layerName
}
}
puts "Layers added to a list... Click in Graphics to continue"
SclPause
# Form definition start here. Details of the form are stored in the "layerSelection" variable.
set layerSelection {
#GuidoForm container has two switches, the label and default_buttons switch.
GuidoForm form {
-label "Select Layer"
-default_buttons
GuidoComboBox layer {
-label "Layer"
-width 15
-exclusive true
-default "design"
}
}
};# Form definition ends here.
# Use the SclCreateGuidoForm command to compile the form into a variable called "formH"
SclCreateGuidoForm formH \\\$layerSelection {
# This populates the combobox with all the layers in the layerList variable
set layer.setValues \\\$layerList
}
\\\$formH SclRun {}
if {"\\\$_status" != "apply"} {
puts "Macro cancelled"
# Normally you would stop the macro if someone pressed cancel but in our example we press on. Just unhash return for normal function. "return" is another TCL command that in this instance will stop the macro.
#return
}
puts "You have selected the \\"\\\$layer\\" layer"
sclGraphicsLayers SclIterateFirst Iterator
# ourSwa is the reference variable that we can use when setting the active layer
while {[\\\$Iterator SclIterateNext ourSwa] == \\\$SCL_TRUE} {
# store the layername into a variable called "layerName"
set layerName [\\\$ourSwa SclGetId]
# Check to see if the current layer stored in \\\$layerName is the one selected which is stored in \\\$layer variable.
if {\\\$layerName == \\\$layer} {
puts "Active layer is now \\\$layer. Check the \\"layers\\" pane to see if this is true."
# If we find the required layer, use the SclSetActiveLayer command to change the active layer referenced by \\\$SwaHandle
\\\$vh SclSetActiveLayer \\\$ourSwa
puts "Click in graphics once layer is confirmed."
SclPause
# no need to search once we have found the layer we are after. Break will exit the while loop.
break
}
}
puts "End of part 3"
####### PART 4 #######
puts ""
puts "Part 4 - Saving a layer then recalling data into a created layer before modifying."
#Saving a layer can be done with a normal recorded "Save Layer" or "Save File" function however SCL provides a way to do it as well.
#Depending on which layer you chose in part 3 will depend on which layer will now be saved.
# This will get the date into a format that the string file header can use
set today [clock format [clock seconds] -format "%d %b %Y"]
#Options variable is a set of parameters separated by the | symbol. Some of the options are styles, binary or text and string range.
set options "header=\\\$layer, \\\$today, Test of SclSwaSaveStringFile, ssi_styles:styles.ssi|axis=0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0|binary=off"
# This is the line of code that will save a string file with your included options.
\\\$ourSwa SclSwaSaveStringFile \\\$layer.str "\\\$options"
#Let's assume we have saved the data we want and need to exit graphics to start another project.
SclFunction "EXIT GRAPHICS" {}
#Now, let's recall your saved string file into a new layer we will call new_design
# Get a reference to the active viewport (You can have more than one) store it in reference variable "vh"
SclGetActiveViewport vh
# Create a layer called new_design that can be manipulated/inquired with the "newDesignSwa" reference variable
SclCreateSwa newDesignSwa "new_design"
# Add the new_design layer into the layers pane so it is visible
sclGraphicsLayers SclAdd \\\$newDesignSwa \\\$vh
# Everything in "" is an option. The option to "load draw styles" will ensure the styles file is used.
\\\$newDesignSwa SclSwaOpenFile \\\$layer.str "load draw styles"
# Make the "new_design" layer active.
\\\$vh SclSetActiveLayer \\\$newDesignSwa
# Get a handle to all the strings in the new_design layer
\\\$newDesignSwa SclGetStrings newDesignStrs
# Draw all the strings in graphics
\\\$newDesignStrs SclDraw
# Whenever you bring data into a layer, you'll generally need to zoom all to see it.
SclFunction "ZOOM ALL" {}
# Now, lets say we wanted to edit a point in the layer to a known coordinate. We first need to get a "handle" to the point.
# We will use "SclSelectPoint" to achieve this. This is a very versatile function that I'll cover in a later QA doco.
# There are many options for editing this point however for this QA I will just move the point 1m East for every click on the point.
# To do this we need to put the command in a while loop.
while {1} {
# Note pointMod below. This is the reference variable that gives me complete access to this point and all data attached to it.
# Note also that the coordinates of the point are stored in the x, y and z variables below as well.
set status [SclSelectPoint pointMod "Click a point to move by 1m East. Press Esc to continue." layerName strNum segNum pntNum x y z desc]
# Using the handle we have to the point in reference variable "pointMod" get a handle to the segment it resides in.
\\\$pointMod SclGetParent segMod
if {\\\$status != "\\\$SCL_OK"} {
puts "Finished moving points"
break
}
# Add 1m to the current x value
\\\$pointMod SclSetValueByName x [expr \\\$x+1]
\\\$segMod SclErase
# Using the handle to the segment, draw the updated coords on the screen.
\\\$segMod SclDraw
}
puts "End of part 4"
# At this point you could exit or save the modifications. We will leave the modified layer in graphics ready for Part 5 of this series.
# Part 5 will cover how to use SCL to loop over all points in a layer.
####### PART 5 #######
puts ""
puts "Part 5 - Using Scl to loop over all points in a layer"
# Get a handle to the viewport
SclGetActiveViewport vh
# Using the viewport handle, get a handle to the SWA (layer)
\\\$vh SclGetActiveLayer SwaH
# Using the handle to the SWA, get a handle to all the strings in the layer
\\\$SwaH SclGetStrings StrsH
# Count how many strings are in the active layer
set strQuantity [\\\$StrsH SclCountItems]
# If there aren't any strings then write a message to the user and stop the macro using the "return" command.
if {\\\$strQuantity <= 0} {
puts "No strings in active layer."
return
}
# Setup a string iterator based on the handle to the strings in "\\\$StrsH"
\\\$StrsH SclIterateFirst StringsIterator
#While there are strings to iterate, keep going
while {[\\\$StringsIterator SclIterateNext StringHandle] == \\\$SCL_TRUE} {
#Use SclGetId to work out the string number and print it to the message window
puts "String number = [\\\$StringHandle SclGetId]"
# Setup a segment iterator based on the handle to the string in "\\\$StringHandle"
\\\$StringHandle SclIterateFirst StringIterator
# While there are segments to iterate over in the current string, keep going
while {[\\\$StringIterator SclIterateNext SegmentHandle] == \\\$SCL_TRUE} {
#Remember, we add one to the segment number because segments work from an index position which starts at zero.
puts "Segment number = [expr [\\\$SegmentHandle SclGetId]+1]"
# Setup a point iterator based on the handle to the segment in "\\\$SegmentHandle"
\\\$SegmentHandle SclIterateFirst SegmentIterator
set PointCount 1
# While there are points in the segment to iterate over, keep going.
while {[\\\$SegmentIterator SclIterateNext PointHandle] == \\\$SCL_TRUE} {
set x [\\\$PointHandle SclGetValueByName x]
set y [\\\$PointHandle SclGetValueByName y]
set z [\\\$PointHandle SclGetValueByName z]
set d1 [\\\$PointHandle SclGetValueByName d1]
puts "Point \\\$PointCount X = \\\$x, Y = \\\$y, Z = \\\$z, D1 = \\\$d1"
incr PointCount
}
}
}
puts "You can also iterate backwards by changing SclIterateFirst for SclIterateLast"
puts "AND SclIterateNext for SclIteratePrev. There are several reasons for needing to do this especially when deleting strings"
\\\$StrsH SclIterateLast StringsIterator
while {[\\\$StringsIterator SclIteratePrev StringHandle] == \\\$SCL_TRUE} {
puts "String number = [\\\$StringHandle SclGetId]"
\\\$StringHandle SclIterateLast StringIterator
while {[\\\$StringIterator SclIteratePrev SegmentHandle] == \\\$SCL_TRUE} {
puts "Segment number = [expr [\\\$SegmentHandle SclGetId]+1]"
\\\$SegmentHandle SclIterateLast SegmentIterator
set PointCount 1
while {[\\\$SegmentIterator SclIteratePrev PointHandle] == \\\$SCL_TRUE} {
set x [\\\$PointHandle SclGetValueByName x]
set y [\\\$PointHandle SclGetValueByName y]
set z [\\\$PointHandle SclGetValueByName z]
puts "Point \\\$PointCount X = \\\$x, Y = \\\$y, Z = \\\$z"
incr PointCount
}
}
}
#There are many things that can be done with this simple looping code.
#1. Write points to a csv file
#2. Modify the z value of points in a segment
#3. Write points inside a boundary to a new layer
#4. Identify points by inquiring there dfields.
puts ""
puts "End of part 5"
puts "Part 6 will cover how to use Surpac ranges. While no data is actually needed, the code will check for it so keep it in graphics for now."
####### PART 6 #######
#Part 6
puts ""
puts "Part 6 - How to code Surpac Ranges using TCL/SCL."
# Get a handle to the viewport
SclGetActiveViewport vh
# Using the viewport handle, get a handle to the SWA (layer)
\\\$vh SclGetActiveLayer SwaH
# Using the handle to the SWA, get a handle to all the strings in the layer
\\\$SwaH SclGetStrings StrsH
# Count how many strings are in the active layer
set strQuantity [\\\$StrsH SclCountItems]
# If there aren't any strings then write a message to the user and stop the macro using the "return" command.
if {\\\$strQuantity <= 0} {
puts "No strings in active layer."
return
}
# The range below would expand to 1,3,5,7,9
puts "Example range below"
set myRange "1,10,2"
# Print the range to the message window
puts \\\$myRange
# Place all the expanded components into something equivalent to a TCL list
set status [SclRangeExpand handle \\\$myRange]
# Count how many items are in the range now it is a list
set count [SclRangeGetCount \\\$handle]
puts "The example range expands to the following:"
# Loop over each item in the range extracting the unique string number as you go.
for {set i 0} {\\\$i < \\\$count} {incr i} {
# Store the item at index i into a variable called "value"
set status [SclRangeGet \\\$handle \\\$i value];
# The value always comes from the list in "double" format i.e. it has a decimal -> 1 is 1.0 NINT removes the decimal
set value [SclExpr NINT(\\\$value)]
puts "The range value at index \\\$i is \\\$value"
}
# Remove the range handle from memory
SclDestroy handle
# Now have a go at entering your own range in the GUIDO form.
set rangeForm {
GuidoForm form {
-label "Range Finder"
-default_buttons
GuidoField myRange {
-label "Enter Range"
-width 20
-format range
-null false
-tip "Enter a valid Surpac range. i.e 1,10,2 or 1;5;23"
}
}
}
SclCreateGuidoForm formH \\\$rangeForm {}
\\\$formH SclRun {}
if {"\\\$_status" != "apply"} {
puts "Macro Cancelled"
return
}
puts ""
puts "Your range is as below"
set status [SclRangeExpand handle \\\$myRange];# Place all the expanded components into something equivalent to a TCL list
set count [SclRangeGetCount \\\$handle];# Count how many items are in the range now it is a list
for {set i 0} {\\\$i < \\\$count} {incr i} {;# Loop over each item in the range extracting the unique string number as you go.
set status [SclRangeGet \\\$handle \\\$i value];# Store the item at index i into a variable called "value"
set value [SclExpr NINT(\\\$value)];# The value always comes from the list in "double" format i.e. it has a decimal -> 1 is 1.0 NINT removes the decimal
puts "The range value at index \\\$i is \\\$value"
}
SclDestroy handle;# Remove the handle from memory
puts "End of Part 6. The next part in this series will cover TCL lists."
###### PART 7 #######
#Let's assume we have saved the data we want and need to exit graphics to start another project.
SclFunction "EXIT GRAPHICS" {}
puts ""
puts "Part 7 - TCL lists for storing information"
set shoppingList {}
#Add items to our list with the lappend command
lappend shoppingList bacon
lappend shoppingList eggs
lappend shoppingList bread
lappend shoppingList meat
lappend shoppingList tomatoes
lappend shoppingList potatoes
lappend shoppingList onion
lappend shoppingList cheese
set item [lindex \\\$shoppingList 3]
#Write to the message window and then add a blank line for readability.
puts "Item at index position 3 is \\\$item"
puts ""
#foreach is a special TCL list command designed specifically to iterate over all items in a list, one by one.
set position 0
foreach item \\\$shoppingList {
puts "Item \\\$position is \\\$item"
incr position
}
puts ""
#Use the variable "shoppingListLength" to store the number of items in the list
set shoppingListLength [llength \\\$shoppingList]
puts "There are \\\$shoppingListLength items in your shopping list."
puts ""
puts "Now lets look at lists of lists"
#I have created a list (coordList) and stored four points in it with each point having an x and y value.
set coordList [list {100 100} {100 200} {200 200} {200 100}]
set point3 [lindex \\\$coordList 2]
#point3 is it's own list with the x coord in index 0 and the y coord in index 1
puts "Extract out a single value"
set point3X [lindex \\\$point3 0]
set point3Y [lindex \\\$point3 1]
puts "Point 3 coords -> X = \\\$point3X, Y = \\\$point3Y"
puts ""
#Now let's iterate over all points in the coordList
set pointNum 1
puts "Extract values for all points in the list"
foreach point \\\$coordList {
set pointX [lindex \\\$point 0]
set pointY [lindex \\\$point 1]
puts "Point \\\$pointNum coords -> X = \\\$pointX, Y = \\\$pointY"
incr pointNum
}
More Tips:
