added plot_methos.jl

docs/src/pages/fits.md

@@ -69,4 +69,15 @@ cast_FORTRAN_format(str::String)
 ```@docs
 FORTRAN_eltype_char(T::Type)
 parse_FITS_TABLE(hdu::FITS_HDU)
+```
+
+## Plotting
+
+```@docs
+step125(x::Real)
+select125(x)
+steps(x::Vector{T} where T<:Real)
+stepcenters(x::Vector{T} where T<:Real)
+stepedges(x::Vector{T} where T<:Real)
+edges(px, Δx=1.0, x0=0.0)
 ```

src/CamiFITS.jl

@@ -162,6 +162,13 @@ export test_fits_edit_key!
 export test_fits_delete_key!
 export test_fits_rename_key!
 
+export step125
+export select125
+export steps
+export stepcenters
+export stepedges
+export edges
+
 include("julia_toolbox.jl")
 include("fits_objects.jl")
 include("dicts.jl")
@@ -173,5 +180,6 @@ include("fits_public_sector.jl")
 include("FORTRAN.jl")
 include("fits_tests.jl")
 include("test_fits_format.jl")
+include("plot_methods")
 
 end

src/plot_methods.jl

@@ -0,0 +1,143 @@
+# SPDX-License-Identifier: MIT
+
+# author: Jook Walraven - 14-2-2023
+
+# ==============================================================================
+#                               plot_methods.jl
+# ==============================================================================
+
+# ==================================== step125(x) ============================================================
+
+"""
+    step125(x)
+
+Step used for deviding the number x in steps according to 1-2-5 scheme
+#### Examples:
+```
+step125.([5,10,21.3,50,100.1])
+5-element Vector{Int64}:
+  1
+  2
+  5
+ 10
+ 20
+```
+"""
+function step125(x::Real) 
+
+    m = CamiMath.log10_mantissa(x)
+    p = CamiMath.log10_characteristic(x)
+    v = 10^m
+    d = v > 7.9 ? 2.0 : v > 3.9 ? 1.0 : v > 1.49 ? 0.5 : 0.2
+
+    return max(1,round(Int, d *= 10^p))
+
+end
+
+# ==================================== select125(x) ===============================================================
+
+"""
+    select125(x)
+
+Select elements of the collection x by index according to 1-2-5 scheme
+#### Examples:
+```@docs
+x = [1,2,4,6,8,10,13,16,18,20,40,60,80,100]
+select125(x)
+ [2, 6, 10, 16, 20, 60, 100]
+
+x = string.(x)
+select125(x)
+ ["2", "6", "10", "16", "20", "60", "100"]
+
+x = 1:100
+select125(x)
+ [20, 40, 60, 80, 100]
+```
+"""
+select125(x) = (n = length(x); return [x[i] for i=step125(n):step125(n):n])
+
+# ==================================== edges(x) ===============================================================
+
+"""
+    edges(px [, Δx[, x0]])
+
+Heatmap range transformation from pixel coordinates to physical coordinates,
+with pixelsize Δx and offset x0, both in physical units.
+#### Examples:
+```@docs
+px = 1:5
+Δx = 2.5
+x0 = 2.5
+edges(px)
+ [0.5, 1.5, 2.5, 3.5, 4.5]
+
+edges(px, Δx)
+ [1.25, 3.75, 6.25, 8.75, 11.25]
+
+edges(px, Δx, x0)
+ [-1.25, 1.25, 3.75, 6.25, 8.75]
+```
+"""
+edges(px, Δx=1.0, x0=0.0) = collect(px .* Δx) .-(x0 + 0.5Δx)
+
+# =================================== steps(x) =============================================================
+
+"""
+    steps(x)
+
+Heatmap range transformation for steplength specification vector x
+#### Examples:
+```@docs
+x = [4,2,6]
+steps(x)
+ [0, 4, 6, 12]
+```
+"""
+function steps(x::Vector{T} where T<:Real)
+
+    sum(x .< 0) == 0 || error("Error: $x - nagative step length not allowed")
+
+    return (s = append!(eltype(x)[0],x); [Base.sum(s[1:i]) for i ∈ Base.eachindex(s)])
+
+end
+
+# =================================== stepcenters(x) =============================================================
+
+"""
+    stepcenters(x)
+
+Stepcenter positions for steplength specification vector x
+#### Examples:
+```@docs
+x = [4,2,6]
+stepcenters(x)
+ [2.0, 5.0, 9.0]
+```
+"""
+function stepcenters(x::Vector{T} where T<:Real)
+
+    s = append!(eltype(x)[0],x)
+
+    return [Base.sum(s[1:i]) + 0.5x[i] for i ∈ Base.eachindex(x)]
+
+end
+
+# =================================== stepedges(x) =============================================================
+
+"""
+    stepedges(x)
+
+Stepedges for steplength specification vector x
+#### Examples:
+```@docs
+x = [4,2,6]
+stepedges(x)
+ [0, 4, 6, 12]
+```
+"""
+function stepedges(x::Vector{T} where T<:Real)
+
+    return steps(x)
+
+end

test/runtests.jl

@@ -66,4 +66,11 @@ using Dates
     @test fits_terminology("s"; test=true)
     @test fits_terminology(; test=true)
 
+    @test edges(1:5, 2.5, 2.5) == [-1.25, 1.25, 3.75, 6.25, 8.75]
+    @test steps([4, 2, 6]) == [0, 4, 6, 12]
+    @test stepcenters([4, 2, 6]) == [2.0, 5.0, 9.0]
+    @test stepedges([4, 2, 6]) == [0, 4, 6, 12]
+    @test select125([1, 2, 4, 6, 8, 10, 13, 16, 18, 20, 40, 60, 80, 100]) == [2, 6, 10, 16, 20, 60, 100]
+    @test step125.([5, 10, 21.3, 50, 100.1]) == [1, 2, 5, 10, 20]
+
 end