counting rows based on values in another column

[#1]

I have a column that defines a grouping, like a column called 'gender' that contains the values 'male' and 'female'. I want to know how many rows in the dataset = 'male' and how many rows in the dataset = 'female'.

[#2 · Accepted solution]

dt = current data table();

dt << Select Where(:Gender == "male");

male = nrows(dt << Get Selected rows());

dt << Select Where(:Gender == "female");

female = nrows(dt << Get Selected rows());

[#3 · Accepted solution]

You can use Tables > Summary.  Here's a JSL version:

dt = open("$sample_data/Big Class.jmp");

dt << Summary( Group( :sex ), N );

There's also the SUMMARIZE command in JSL.  You need a numeric column to get this to work though:

summarize(gsex = by(:sex), gcount = count(:height));

print(gcount);

[18, 22]

[#4]

Thank you for these responses. Is there any way to do this within a column formula?

[#5]

Col Number(Row(), :Gender)

[#6]

Thanks! This helped me out.