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deltaCIP

Calculate Celestial Intermediate Pole (CIP) location adjustment

Description

example

DCIP=deltaCIP(utc) calculates the adjustment to location of the Celestial Intermediate Pole (CIP) for a specific Universal Coordinated Time (UTC), specified as a modified Julian date. By default, this function uses a prepopulated list of IAU 2000A Earth orientation (IERS) data. This list contains measured and calculated (predicted) data supplied by the IERS. The IERS measures and calculates this data for a set of predetermined dates.

[DCIP,DCIPError]=deltaCIP(utc) returns the error for the adjustment to location of the CIP.

example

DCIP=deltaCIP(utc,Name,Value) calculates the location of the CIP using additional options specified by one or more Name,Value pair arguments.

[DCIP,DCIPError]=deltaCIP(utc,Name,Value) returns the error for the adjustment to location of the CIP.

Examples

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Calculate the CIP adjustment for December 28, 2015. Use the mjuliandate function to calculate the date as a modified Julian date.

mjd = mjuliandate(2015,12,28)
dCIP = deltaCIP(mjd)
mjd =
       57384
dCIP =
   1.0e-09 *
   -0.3927    0.0145

Calculate the CIP adjustment and CIP adjustment error for December 28, 2015 and January 10, 2016 using the aeroiersdata.mat file. Use the mjuliandate function to calculate the date as a modified Julian date.

mjd = mjuliandate([2015 12 28;2016 1 10])
[dCIP,dCIPErr] = deltaCIP(mjd,'Source','aeroiersdata.mat')
mjd =
       57384
       57397
dCIP =

   1.0e-08 *

   -0.0393    0.0015
   -0.0087   -0.1110

dCIPErr =
   1.0e-09 *
    0.5769    0.1842
    0.2376    0.4121

Input Arguments

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Array of UTC dates, specified as an M-by-1 array, represented as modified Julian dates. Use the mjuliandate function to convert the UTC date to a modified Julian date.

Data Types: double

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Before R2021a, use commas to separate each name and value, and enclose Name in quotes.

Example: 'Source','aeroiersdata.mat'

Custom list of Earth orientation data, specified in a MAT-file.

Out-of-range action, specified as a string.

Action to take in case of out-of-range or predicted value dates, specified as a string:

  • Warning — Displays warning and indicates that the dates were out-of-range or predicted values.

  • Error — Displays error and indicates that the dates were out-of-range or predicted values.

  • None — Does not display warning or error.

Data Types: string

Output Arguments

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Adjustment ([dDeltaX,dDeltaY]) to location of the Celestial Intermediate Pole (CIP), specified as an M-by-2 array, in radians.

Error for adjustment to location of the CIP, specified as an M-by-2 array, in radians.

Version History

Introduced in R2018b

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Behavior changed in R2020b