# FREQ1

Bulk Data Entry Defines a set of frequencies to be used in the solution of frequency response problems by specification of a starting frequency, frequency increment, and the number of increments desired.

## Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
FREQ1 SID F1 DF NDF

## Example

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
FREQ1 6 2.9 0.5 13

## Definitions

Field Contents SI Unit Example
SID Set identification number.

No default (Integer > 0)

F1 First frequency in set.

No default (Real ≥ 0)

DF Frequency increment.

No default (Real > 0.0)

NDF Number of frequency increments.

Default = 1 (Integer > 0)

1. FREQ1 entries must be selected with the I/O Options or Subcase Information command FREQUENCY = SID.
2. The units for F1 and DF are cycles per unit time.
3. The frequencies defined by this entry are given by fi = F1 + DF * (i -1)

where i = 1 to (NDF + 1).

4. All FREQi entries with the same set identification numbers will be used. Duplicate frequencies will be ignored. ${f}_{N}$ and ${f}_{N-1}$ are considered duplicated if:(1)
$|{f}_{N}-{f}_{N-1}|<\mathit{DFREQ}*|{f}_{\mathit{MAX}}-{f}_{\mathit{MIN}}|$
Where,
DFREQ
User parameter with a default of 10-5 * ${f}_{MAX}$
${f}_{MIN}$
The maximum and minimum excitation frequencies of the combined FREQi entries
5. This card is represented as a load collector in HyperMesh.