Working with Arrays

Caliper Script contains a number of functions you can use to create and manipulate arrays. In addition, the + operator concatenates two arrays.

GISDK Function	Summary
ArrayElementToInteger()	Converts an array element to an integer
ArrayElementToReal()	Converts an array element to a real number
ArrayElementToString()	Converts an array element to a string
ArrayExclude()	Excludes elements from an array
ArrayIntersect()	Creates an array that contains the elements of the array a that are also in array b
ArrayLength()	Computes the number of elements in an array
ArrayMax()	Determines the largest value in an array of numbers
ArrayMin()	Determines the smallest value in an array of numbers
ArrayPosition()	Finds the position of a sub-array in an array
Avg()	Computes the average value of the elements of an array
CompareArrays()	Compares two arrays, element by element
CopyArray()	Makes a copy of the array, including nested sub-arrays, to any depth
ExcludeArrayElements()	Removes elements from an array
ExtractArray()	Returns the specified sub-array, which must itself be an array
FindOption()	Finds a particular option and its setting in an array of name-value pairs
FindOptionValue()	Finds the value of a particular option in an options array
FindStrings()	Finds strings in an array that match one or more search specs
GetArrayScope()	Returns the scope of an array of coordinates
InsertArrayElements()	Inserts elements into an array
JsonToArray()	Converts a proper JSON literal object to an options array
Kurtosis()	Returns the kurtosis of a set of numbers
LoadArray()	Loads an array from a file
Mean()	Computes the mean (average) of the elements of an array
Median()	Computes the median of the elements of an array
Percentile()	Returns the value at which a given percentile is reached
ReadArray()	Reads a text file into an array of strings
ReadSizedArray()	Reads a group of strings from a file
ReverseArray()	Returns a new array, with the same elements as the input array, but in the reverse order
SaveArray()	Saves an array to a file
ShowArray()	Displays a Windows dialog box containing the contents of an array, including nested sub-arrays
Skew()	Returns the skew of the values in an array
SortArray()	Sorts the elements of an array
Std()	Computes the standard deviation of an array of numbers
Subarray()	Extracts a number of elements from an array
Sum()	Computes the sum of an array of numbers
TransposeArray()	Transposes an array of arrays, where element b[i][j] = a[j][i]
Var()	Returns the variance on an array of numbers
WriteArray()	Writes the elements of an array to a text file
WriteArraySeparated()	Writes the elements of an array to a file, separated by a delimiter

You can determine the length of an array using ArrayLength() or using the special syntax arrayname.length, as in:

n = names.length

ShowMessage ("There are " + String(n) + " names in the list")

Since you can concatenate arrays, you can increase the size of an array. Here an example, using array x from above:

x = { "New York", "Los Angeles", "Miami"}

y = { "Seattle", "Atlanta"}

x = x + y // x[4] equals "Seattle"

If you change the original array, the array that it is concatenated to will also be changed:

y[2] = {"Chicago"} // x[5] is now "Chicago" as well

To make a completely new copy of an array, use CopyArray().

You can build an array of any length at runtime by concatenating the desired number elements to the array. Note that a variable or array element must be placed in an array to do the concatenation:

window_array = GetWindows("All") // returns an array containing three arrays

map_names = null // initialize the variable for the new array

for i = 1 to window_array[2].length do

if window_array[2][i] = "Map" // type in second sub-array, name in first

then map_names = map_names + { window_array[1][i] }

end

Also note that this is very inefficient if the array may be large and you can dimension the array first. This executes slowly:

slow_array = null

for i = 1 to 1000 do

slow_array = slow_array + {i}

end

This executes much faster: