Fortran How Do I Determine Single-Precision Machine Constants in Fortran?

AI Thread Summary
The discussion centers on determining the "Single-Precision Machine Constants" (R1MACH) for a program written in Fortran, specifically for a desktop computer with an Intel Pentium Dual Core processor running Windows Vista. The user seeks assistance in calculating R1MACH values from 1 to 5, which include the smallest positive magnitude, largest magnitude, smallest relative spacing, largest relative spacing, and the logarithm base 10 of the base (B). The code references a framework for a portable library and cites relevant literature for further context. Participants are encouraged to provide insights or calculations to help resolve the user's issue with these machine constants.
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Help!
I know almost nothing about Fortran but need to use a program by others. I encountered a problem in determining the "Single-Precision Machine Constants" for my desktop computer (intel pentium dual core 5200 2mb l2 2.5ghz 800 fsb with Window Vista). Please take a look at following part or comment in the code. Could anyone help me to determne R1MACH(1 to 5)?

C Single-Precision Machine Constants r1mach27
C R1MACH(1) = B**(EMIN-1), the smallest positive magnitude. r1mach28
C R1MACH(2) = B**EMAX*(1 - B**(-T)), the largest magnitude. r1mach29
C R1MACH(3) = B**(-T), the smallest relative spacing. r1mach30
C R1MACH(4) = B**(1-T), the largest relative spacing. r1mach31
C R1MACH(5) = LOG10(B) r1mach32
C***REFERENCES FOX, P.A., HALL, A.D., SCHRYER, N.L, *FRAMEWORK FOR r1mach33
C A PORTABLE LIBRARY*, ACM TRANSACTIONS ON MATHE- r1mach34
C MATICAL SOFTWARE, VOL. 4, NO. 2, JUNE 1978, r1mach35
C PP. 177-188. r1mach36
 
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