hist_earliest

Cascade Historian: Version 4.1
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# `hist_earliest`

`hist_earliest` -- gives the earliest value in a history

## Syntax

    hist_earliest (hist_task, history)

## Parameters

`hist_task`

  The task object corresponding to the Cascade Historian. See `locate_task` in the Gamma manual.

`history`

  The name of the history to be queried.

## Returns

An instance of the `HI_stVALUE` class containing the (`value`, `xaxis`) data. Otherwise returns `nil` and sets `_last_error_` to the error string returned by the Cascade Historian.

## Description

This function returns the value for the first data item in the history. This item may be either in a file or in memory.

This function corresponds to the earliest command, and the Cogent API function `HI_Earliest`.

## Example

        Gamma> a = hist_earliest (tsk, "p3");
        {HI_stVALUE (value . 38.2) (xaxis . 973636953.463209)}
        Gamma> a.value;
        38.2
        Gamma> a.xaxis;
        973636953.463209

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