Curve file
Curve files are used to store tables of data, and are widely used in the LS-DYNA peripheral programs supplied by Oasys. A curve file is a text file with tabs, commas or spaces separating fields.
Curve file
The format of the file is as follows:
Title
X label <TYPE/FACTOR>;
Y label <TYPE/FACTOR>;
Curve identifier
x0, y1
x1, y1
…
CONTINUE
Title
X label <TYPE/FACTOR>;
Y label <TYPE/FACTOR>;
Curve identifier
x0, y1
x1, y1
…
By default TYPE is undefined and the FACTOR is 1. This is to allow backwards compatibility in that old programs reading curve files would not require any modification: the labels would just give some additional information. Newer versions would be able to read this information and give tighter control over the data.
Unit types
The current options for TYPE are:
| UNDEFINED | 1ST_MOMENT_AREA | ANGULAR_ACCELERATION |
| FORCE | 2ND_MOMENT_AREA | FLOW_RATE |
| LENGTH | VOLUME | FREQUENCY |
| MASS | PER_LENGTH | ANGULAR_FREQUENCY |
| TIME | PER_AREA | PERIOD |
| TEMPERATURE | PER_VOLUME | THERMAL_EXPANSION |
| DISP | CS_AREA | TEMPERATURE_GRADIENT |
| PRESSURE | CS_AREA_PER_LENGTH | IMPULSE |
| ACCEL | INERTIA | MOMENTUM |
| WORK | DENSITY | ANGULAR_MOMENTUM |
| MOMENT | AREA_DENSITY | DAMPING |
| STRESS | WEIGHT_DENSITY | ENERGY |
| FORCE_PER_LENGTH | MASS_PER_LENGTH | ENERGY_DENSITY |
| MOMENT_PER_LENGTH | PER_MASS | DEGREE |
| MOMENT_PER_ROTATION | VELOCITY | PERCENT |
| STRAIN | ROTATION | |
| AREA | ANGULAR_VELOCITY |
The FACTOR is the value by which the data values should be multiplied to convert to SI units (e.g. 0.01 for cm).
Example
Test curve
Time <TIME>;
Relative acceleration <ACCELERATION/0.001>;
Reference point 1
0, 0
1, 1
2, 4
3, 9
4, 16