if(condition, result_if_true, result_if_false)

Evaluates the condition and returns
result_if_true if the condition evaluates to true or
result_if_false if the condition evaluates to
false .
condition must be a number. This function considers
0 and an empty string as
false
and everything else (including NaN ) as
true .
Booleans convert to 0 (false) and 1 (true).
You can return the none constant
from this function to discard the output for a particular condition. This
means you can filter out data points that don't meet a condition. For more
information, see Filtering data points.
Examples

if(0, x, y) returns the variable
y .

if(5, x, y) returns the variable
x .

if(gt(temp, 300), x, y) returns the variable
x if the variable temp is greater than
300 .

if(gt(temp, 300), temp, none) returns the variable
temp if it's greater than or equal to 300 ,
or none (no value) if temp is less than
300 .
We recommend that you use UFCS for nested conditional functions where
one or more arguments are conditional functions. You can use
if(condition, result_if_true) to evaluate a condition and
elif(condition, result_if_true, result_if_false) to evaluate
additional conditions.
For example, you can use if(condition1,
result1_if_true).elif(condition2, result2_if_true,
result2_if_false) instead of if(condition1, result1_if_true,
if(condition2, result2_if_true, result2_if_false)) .
You can also chain additional intermediate conditional functions. For
example, you can use if(condition1, result1_if_true).elif(condition2,
result2_if_true).elif(condition3, result3_if_true,
result3_if_false) instead of nesting multiple if
statements, such as if(condition1, result1_if_true, if(condition2,
result2_if_true, if(condition3, result3_if_true
result3_if_false))) .
You must use elif(condition, result_if_true,
result_if_false) with UFCS.
