repl.txt (1680B)
1 2 {{alias}}( x, μ, σ ) 3 Evaluates the natural logarithm of the probability density function (PDF) 4 for a lognormal distribution with location parameter `μ` and scale parameter 5 `σ` at a value `x`. 6 7 If provided `NaN` as any argument, the function returns `NaN`. 8 9 If provided `σ <= 0`, the function returns `NaN`. 10 11 Parameters 12 ---------- 13 x: number 14 Input value. 15 16 μ: number 17 Location parameter. 18 19 σ: number 20 Scale parameter. 21 22 Returns 23 ------- 24 out: number 25 Evaluated logPDF. 26 27 Examples 28 -------- 29 > var y = {{alias}}( 2.0, 0.0, 1.0 ) 30 ~-1.852 31 > y = {{alias}}( 1.0, 0.0, 1.0 ) 32 ~-0.919 33 > y = {{alias}}( 1.0, 3.0, 1.0 ) 34 ~-5.419 35 > y = {{alias}}( -1.0, 4.0, 2.0 ) 36 -Infinity 37 38 > y = {{alias}}( NaN, 0.0, 1.0 ) 39 NaN 40 > y = {{alias}}( 0.0, NaN, 1.0 ) 41 NaN 42 > y = {{alias}}( 0.0, 0.0, NaN ) 43 NaN 44 45 // Non-positive scale parameter `σ`: 46 > y = {{alias}}( 2.0, 0.0, -1.0 ) 47 NaN 48 > y = {{alias}}( 2.0, 0.0, 0.0 ) 49 NaN 50 51 52 {{alias}}.factory( μ, σ ) 53 Returns a function for evaluating the natural logarithm of the probability 54 density function (PDF) of a lognormal distribution with location parameter 55 `μ` and scale parameter `σ`. 56 57 Parameters 58 ---------- 59 μ: number 60 Location parameter. 61 62 σ: number 63 Scale parameter. 64 65 Returns 66 ------- 67 logpdf: Function 68 Logarithm of probability density function (PDF). 69 70 Examples 71 -------- 72 > var mylogPDF = {{alias}}.factory( 4.0, 2.0 ); 73 > var y = mylogPDF( 10.0 ) 74 ~-4.275 75 > y = mylogPDF( 2.0 ) 76 ~-3.672 77 78 See Also 79 -------- 80