GRIBv2 - Code Table 4.240

GRIB2 - CODE TABLE 4.240

Type of Distribution Function

Revised 07/07/2017

Code Figure
Meaning

0 No specific distribution function given

1 Delta functions with spatially variable concentration and fixed diameters D_l(p₁) in meter (See Note 1)

2 Delta functions with spatially variable concentration and fixed masses M_l(p₁) in kg (See Note 2)

3 Gaussian (Normal) distribution with spatially variable concentration and fixed mean diameter D_l(p₁) and variance δ (p₂) (See Note 3)

4 Gaussian (Normal) distribution with spatially variable concentration, mean diameter and variance (See Note 4)

5 Log-normal distribution with spatially variable number density, mean diameter and variance (See Note 5)

6 Log-normal distribution with spatially variable number density, mean diameter and fixed variance δ (p₁) (See Note 6)

7 Log-normal distribution with spatially variable number density and mass density and fixed variance δ and fixed particle density ρ (p₂) (See Note 7)

8 No distribution function. The encoded variable is derived from variables characterized by type of distribution function of type No. 7 (see above) with fixed variance σ (p1) and fixed particle density ρ (p2)

9-49151 Reserved

49152-65534 Reserved for Local Use

65535 Missing

Notes:
(1) Bin-Model or delta function with N concentration c_l(r) in class (or mode) l.
Concentration-density function:
ƒ(r;d) = ∑_l=1^N c_l(r) δ (d-D_l)

Where:
N - number of modes in the distribution
δ - delta-Function
d - diameter
D_l - diameter of mode l(p₁)i

(2) Bin-Model or delta function with N concentration c_l(r) in class (or mode) l.
Concentration-density function:
ƒ(r;m) = ∑_l=1^N c_l(r) δ (m-M_l)

Where:
N - number of modes in the distribution
δ - delta-Function
m - mass
M_l - mass of mode (p₁)

(3) N-Modal concentration-density function consisting of Gaussian-functions:
Concentration-density function:
ƒ(r;d) = ∑_l=1^N c_l(r) 1/_{√ 2πδ_l
* e^{-((d-D_l)/δ_l)²}}
Where:
N - number of modes in the distribution
d - diameter
D_l - mean diameter of mode l(p₁)
δ_l - Variance of Mode l ((p₂)
with N fields of concentration c_l(r)

(4) N-Modal concentration-density function consisting of Gaussian-functions:
Concentration-density function:
ƒ(r;d) = ∑_l=1^Nc_l(r)1/_{√ 2πδ_l(r)
* e^{-((d-D_l)(r)/δ_l(r))²}}
Where:
N - fields of concentration c_l(r)
δ_l(r) - Variance
D_l(r) - mean diameter

Back

Code Figure	Meaning
0	No specific distribution function given
1	Delta functions with spatially variable concentration and fixed diameters D_l(p₁) in meter (See Note 1)
2	Delta functions with spatially variable concentration and fixed masses M_l(p₁) in kg (See Note 2)
3	Gaussian (Normal) distribution with spatially variable concentration and fixed mean diameter D_l(p₁) and variance δ (p₂) (See Note 3)
4	Gaussian (Normal) distribution with spatially variable concentration, mean diameter and variance (See Note 4)
5	Log-normal distribution with spatially variable number density, mean diameter and variance (See Note 5)
6	Log-normal distribution with spatially variable number density, mean diameter and fixed variance δ (p₁) (See Note 6)
7	Log-normal distribution with spatially variable number density and mass density and fixed variance δ and fixed particle density ρ (p₂) (See Note 7)
8	No distribution function. The encoded variable is derived from variables characterized by type of distribution function of type No. 7 (see above) with fixed variance σ (p1) and fixed particle density ρ (p2)
9-49151	Reserved
49152-65534	Reserved for Local Use
65535	Missing