Loading data with -9999 as NaN

Load the data normally into some wave say, wave1. Make sure that it is SP or DP. After loading execute the following commands:

Redimension/S wave1  // for SP
MatrixOP/O wave1=Replace(wave1,-9999,NaN)

I hope this helps,

A.G.
WaveMetrics, Inc.

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I believe the 9999 business is a Fortran convention.

If your file is Fortran format (each column of numbers in a fixed field of characters), you can load it as "Fixed Field" which does have the option of treating 9999 as NaN. This is the last parameter of the LoadWave /F field. For details execute:

DisplayHelpTopic "Loading Fixed Field Text Files"

I'm not sure if it works with -9999.

Another approach is to convert -9999 to NaN after loading the data. Here is an example:

Make/O test = {1, 2, 3, -9999, 5, 6}
Edit test
test = test==-9999 ? NaN : test    // You need the space around the colon

For documentation on the ?: operator execute:

DisplayHelpTopic "? :"   // Note there is a space between ? and :

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Thank you both for the quick reply.
hrodstein the 9999 is indeed from a Fortran piece of software however the data is further formatted into CSV with varying column lengths (due to column labels) after the initial computation in Fortran therefore I cannot use the fixed file format loading.
I think I will go with A.G. suggestion to use the Replace operation on the matrix.

Thanks again and enjoy your weekends.

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