Extreme Wind Speeds Software: Fortran Code for Hurricane
This page describes Fortran-77 code that can be used to
analyze the hurricane data sets.
This code is freely downloadable (see below). The computed
quantities are saved in an ASCII file that can be imported
into other programs for plotting and further analysis.
We provide a pre-compiled executable for Windows 2000/XP
platforms. You can compile this code yourself for other
platforms if you have a Fortran-77/90/95 compiler available.
If you have a Fortran-77/90/95 compiler, you can modify this code
with minimal effort to analyze other data sets.
What the Program Computes
Given an input file, xxxx.txt, this program generates the
following two files:
This file contains a table for each value of the
threshold parameter. This table contains:
- The DeHaan estimates for the shape and scale
parameters of the generalized Pareto
- The wind speeds corresponding to mean return
intervals of 50, 2000, 10000, and 100000
- The maximum wind speed for the fitted
- Load factors corresponding to each of the mean
For each value of the threshold, the following
values are written to the file:
- the threshold value
- the number of values above the threshold
- the estimate of the shape parameter
- the estimate of the standard deviation of the
- the wind speeds corresponding to each of the
return intervals (4 values)
- the maximum possible wind speed
- the load factors corresponding to each of the
return intevals (4 values)
This file is provided to make it convenient to read the
values into another program for further analysis (e.g.,
a program for plotting the data).
Example under Windows
This section describes how to run the program under the
Windows 2000/XP operating system.
For the sake of discussion, let us assume that you have created
the directory "C:\HURRLDF" and that you have copied the
data file "file10.txt" (which contains the data for mile
post 550) and the program executable "HURRLDF.EXE" to this
To run the program:
The program will then run. After it completes, the following
two files are created:
- Open a command prompt window.
- When you are prompted for the input file name, enter
See the above section for a description of what these files
These files can be viewed using Notepad (or any other
For non-Windows platforms, the instructions are similar.
Just open a terminal window, initiate the program, and
enter the desired data file.
You can download the following:
You can download these files to whatever directory is
convenient for you. These files require no additional
Description of the Source Code
We provide a brief technical overview for those who want to
adapt this Fortran program to other data sets.
Note that we have modified the code from the version that
was previously available on the NIST ftp site. The output
generated from the program is the same. However, the
program was rewritten to be easier to adapt to other
The program contains the following subroutines.
In summary, to adapt this code to your own data sets, do
This is the driver program. Although you should not
need to modify the basic structure of this routine,
you may want to tweak a few things. For example,
you can modify the number of iterations for the
threshold or the values for the mean reccurrence
This routine reads the input data file. This
routine will need to be modified if you are
reading something other than the hurricane data
sets provided on this web site.
This routine generates the DeHaan estimates.
This routine opens the input/output files.
This subroutine performs a sort of the data using
the QuickSort algorithm. Although you can replace
this with your own sort routine, this is an excellent
sort algorithm and there is little to be gained by
- Modify the GETDAT routine to read your own data files.
- Check the HURRLDF routine to set the desired
threshold iterations and recurrence interals.
- Compile the code on your system.
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Date created: 05/02/2005
Last updated: 11/30/2018
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