NASA Ames Metadata Format: FFI 4010

Metadata pertaining to a given NASA Ames formatted data file are recorded in the first lines (header) of the file itself. The header is made of three subsections:

This document gives the format of the header body for FFI 4010.

Symbols used

DX^s		Interval identifier for the s^th independent variable (real number). It is the interval between two successive values of the s^th independent variable if this interval is uniform, i.e. if X^s(m+1)-X^s(m) = X^s(m)-X^s(m-1) for all valid m. For a non-uniform interval, DX^s = 0.
XNAME^s		Name and unit of the s^th independent variable. Not more than 132 characters long.
NX^s		Number of values of X^s for s < 4 (i.e. for the bounded independent variables).
NXDEF^s		Number of values of X^s (for s < 4) which are explicitly defined in the file header (NXDEF^s = 1 or NX^s). If NXDEF^s = NX^s, then X^s is explicit. If NXDEF^s = 1, then X^s is implicit and its values are defined by X^s(i) = X^s(1) + (i-1)*DX^s for all i from 1 to NX^s.
NV		Number of primary dependent variables.
NAUXV		Number of auxiliary dependent variables.
VSCAL_n		Scale factor (real number) for the n^th primary variable. VSCAL_n is the number by which the recorded values of V_n must be multiplied in order to convert it in the unit of measure specified in VNAME_n (see below). If the n^th primary variable is not rescaled, then VSCAL_n = 1.
VMISS_n		Missing value identifier for the n^th primary variable (real number). VMISS_n is a number indicating missing or erroneous values in the record of the n^th primary variable. It must be larger than the maximal "good" value of V_n.
VNAME_n		Name and unit of the n^th primary dependent variable. VNAME_n must not be more than 132 characters long. The unit specified in VNAME_n must be the unit of VSCAL_n*V_n.
ASCAL_a		Scale factor (real number) for the a^th auxiliary variable. ASCAL_a is the number by which the recorded values of A_a must be multiplied in order to convert it in the unit of measure specified in ANAME_a (see below). If the a^th auxiliary variable is not rescaled, then ASCAL_a = 1.
AMISS_a		Missing value identifier for the a^th auxiliary variable (real number). AMISS_a is a number indicating missing or erroneous values in the record of the a^th auxiliary variable. It must be larger than the maximal "good" value of A_a.
ANAME_a		Name and unit of the a^th auxiliary dependent variable. ANAME_a must not be more than 132 characters long. The unit specified in ANAME_a must be the unit of ASCAL_a*A_a.

VSCAL, VMISS and VNAME must be listed in the same order as the one in which the primary variables are recorded in the data section (n ranging from 1 to NV).

Similarly, ASCAL, AMISS and ANAME must be listed in the same order as the one in which the auxiliary variables are recorded in the data section (a ranging from 1 to NAUXV).

Condensed notation

[ DX^s, s=1,4 ]
[ NX^s, s=1,3 ]
[ NXDEF^s, s=1,3 ]
[ X^s(i), i=1,NXDEF^s ] s=1,3
[ XNAME^s ] s=1,4
NV
[ VSCAL_n, n=1,NV ]
[ VMISS_n, n=1,NV ]
[ VNAME_n ] n=1,NV
NAUXV
[ ASCAL_a, a=1,NAUXV ]
[ AMISS_a, a=1,NAUXV ]
[ ANAME_a ] a=1,NAUXV

Expanded notation

DX¹	DX²	DX³	DX⁴
NX¹	NX²	NX³
NXDEF¹	NXDEF²	NXDEF³
X¹(1)	...	X¹(NXDEF¹)
X²(1)	...	X²(NXDEF²)
X³(1)	...	X³(NXDEF³)
XNAME¹
XNAME²
XNAME³
XNAME⁴
NV
VSCAL₁	...	VSCAL_NV
VMISS₁	...	VMISS_NV
VNAME₁
...
VNAME_NV
NAUXV
ASCAL₁	...	ASCAL_NAUXV
AMISS₁	...	AMISS_NAUXV
ANAME₁
...
ANAME_NAUXV

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