ncol in julia

In Julia, to get the number of columns in a matrix or DataFrame, you can use the ncol function. Here's an example:

using DataFrames

# Create a DataFrame
df = DataFrame(A = 1:5, B = 6:10, C = 11:15)

# Get the number of columns
num_cols = ncol(df)

# Print the result
println("Number of columns: ", num_cols)

This will output the number of columns in the DataFrame df.