Hi everyone,

I need to read an INPUT file. I would like to put some comments in my INPUT file but it makes error during reading the INPUT file. How can I read the input data and ignore the comments ?

Thanks MM

Put the comments at the end of the file.

I need to put comment in front of each data.

You can simply read a blank line into a dummy variable. So if your input file looks like:

this is 1 56 this is 2 43 this is 3

I'm pretty sure you can do:

read(,*) dummyvar read(,*) var1 read(,*) dummyvar read(,*) var 2 etc

or you could just either like said above put your comments at the end of the file, or something like this

56 !! this is variable 1 56 !! this is variable 2 34 !! this is variable 3, etc

You should be able to finely tune your reading with the NAMELIST statement.

Jojo, Could u please explain a little more and give an example thanks

Read each line into a character array and then read your input data from the character array. This gives you much more freedom to interpret your input and, in this case, would allow you to inspect the first character to see if it is a comment or not.

READ(UNIT,*)

This reads a line but ignores the data held in it, effectively skipping the line. Probably quite a useful piece of code for you I would say.

NAMELIST is a conventional statement you can find in any reference manual or on the Internet.

It helps you assemble variables to group a record.

Ex:

INTEGER :: aninteger = 4 REAL :: areal = 5. NAMELIST /record1/ aninteger, areal

WRITE(6,NML=record1) should print on your screen: aninteger=4, areal = 5.

It also works for reading.

I also remember that a similar question was asked sometime ago and a forum user gave an very interesting trick by playing with string as a FORMAT command. Unfortunately, I cannot find it.