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Variable Amplitude Supported File Types

The supported formats are:

To download an example .xls multi-sheet loading data file click here.

All formats have the same data recognition rules.
Data is either a histogram or a set of time histories.

Histogram Data:

Histogram data is asssumed to be a To-From matrix. Where:

  • X Axis - To
  • Y Axis - From
To be recognised as a histogram the data must be square.
So histograms must have the same number of rows and columns.

The first cell (A1) is ignored and should generally be blank.
The first row and column define the lower limits of each cell in the x and y dimensions respectively. The x limits must increase from left to right and the y limits from from top to bottom.The first and last cells may be underflows and overflows. These are identified with the tokens uflow, underflow, uflw, oflow, oflw, or overflow.
All remaining cells must be populated with a number.
For example a histogram containing 4 bins whose limits are from -1000 to 1000 is defined as:

-1000.0 -500.0 0.0 500.0
-1000.00000
-500.00000
0.00000
500.01000

It should be noted that the bin limits defined are the lower edge of the bin. So the bin ranges are:

  • Bin 1 : -1000 to -500
  • Bin 2 : -500 to 0
  • Bin 3 : 0 to 500
  • Bin 4 : 500 to 1000

The fatigue software will generally assume the largest cycle that could be formed by the to and from turning points.
So the one cyle shown will be from -1000 to 1000.

Time Histories or Sequential Data:

If the data is not recognised as a histogram then the data will be passed through the history recognition rules.
To be recognised as history data the number of numeric columns is tracked. Non numeric data is treated as a header.
The algorithm searchs for the start of data by skipping rows of data where non-numeric values occur. It then requires
that all subsequent data is numeric and that the number of columns of data should be consistent.
Allowance is made for histories of different lengths.

The example below shows 3 channels of data,
the first with 8 samples,
the second with 4 samples,
and the third with 10 samples.

1000.02000.03000.0
2000.03000.02000.0
3000.02000.01000.0
2000.01000.00.0
1000.0 1000.0
0.0 2000.0
1000.0 3000.0
1000.0 3000.0
2000.0
1000.0


Initial non-numeric rows are ignored. This allows data with a header to be read, the header is ignored.
The above example with a header would look something like

Some text on this line and so on
More Header
Fred ran this test
Etc ...
1000.02000.03000.0
2000.03000.02000.0
3000.02000.01000.0
2000.01000.00.0
1000.0 1000.0
0.0 2000.0
1000.0 3000.0
1000.0 3000.0
2000.0
1000.0


If the numeric data starts on row 2 then the first row is assumed to be a set of data channel names.
The above example with a header would look something like

Gage 23 Pressure 2 Temperature 9
1000.02000.03000.0
2000.03000.02000.0
3000.02000.01000.0
2000.01000.00.0
1000.0 1000.0
0.0 2000.0
1000.0 3000.0
1000.0 3000.0
2000.0
1000.0


EXCEL .xls, .xlx and .xlsb

Currently 3 Excel formats are supported:

  • Excel .xls BIFF 8 (Excel 97-2007)
  • Excel .xlsx (Excel 2007 ASCII)
  • Excel .xlsb (Excel 2007 Binary)

Excel formats support multiple sheets and each sheet is passed through the data recognition rules as a separate entity.
So there may be a histogram on sheet 1 (Channel 0),
  3 load histories on sheet 2 (channels 1-3),
  sheet 3 could not be recognised as load data,
  and sheet 4 has 2 load histories (channels 4-5).


ASCII (any extension excluding .xls)

ASCII data is formed into cells using one of two cell delimiters a comma, or a tab.
Multiple spaces are allowed between columns of data but a single comma or tab is required to denote the end of a column's data.
If a column's data is blank then the trailing comma or tab is still required. This would occur when multiple histories of different
lengths are defined.
The 3 channel time history example above is replicated below in ASCII format using commas as the delimiter.


Gage 23, Pressure 2, Temperature 9
1000.0, 2000.0, 3000.0
2000.0, 3000.0, 2000.0
3000.0, 2000.0, 1000.0
2000.0, 1000.0, 0.0
1000.0,   , 1000.0
0.0,   , 2000.0
1000.0,   , 3000.0
1000.0,   , 3000.0
  ,   , 2000.0
  ,   , 1000.0