error: row number (-1) is not valid.

[#1]

Hi,

I am following the very first example on "hello world' in JMP scripting basic and has encountered error.

script:

for(i=1, i<5, i++,
X=i;
A="Hello, World";
print(X,A));
print("done");

error:

Cannot set value for the column 'X' because the row number (-1) is not valid.

Can anyone enlighten what is wrong with the script?

[#2 · Accepted solution]

[#3]

Seems to run fine ..

[#4 · Accepted solution]

The issue is one of scoping.  JMP is finding your variable 'X: in a data table.....I assume.  And because of that, it is wanting to have a subscript for the X variable.  To make this work and point to the memory variable "X" you need to force the proper reference to it by placing "::" in front of the variable.

For( i = 1, i < 5, i++,
	::X = i;
	A = "Hello, World";
	Print( ::X, A );
);
Print( "done" );