diff --git a/src/yapsut/__init__.py b/src/yapsut/__init__.py
index 708e8b6a827b56f94a494c8d5a877c2bcbc82ac2..77676f02e0499b62f7b8e043d0d7e44bed297ce7 100644
--- a/src/yapsut/__init__.py
+++ b/src/yapsut/__init__.py
@@ -1,5 +1,6 @@
# Created : Thu Dec 1 20:04:27 2022
-from .graphics import odot,ocirc,curveXY2patch,SaveFig,STANDARDFIG,StandardFig
+from .mks import MKS
+from .graphics import odot,ocirc,curveXY2patch,SaveFig,STANDARDFIG,StandardFig, ImshowXT
from .pyblocks import pyBlocks
from .AppendableDict import AppendableDict
from .ya_config import YA_CONFIG
diff --git a/src/yapsut/mks.py b/src/yapsut/mks.py
new file mode 100644
index 0000000000000000000000000000000000000000..6a78e1b7ad16ef130fe8a27eb80dd36422585502
--- /dev/null
+++ b/src/yapsut/mks.py
@@ -0,0 +1,169 @@
+__description__="""
+M.Maris - 2024 Apr 19 -
+
+Definition of relevant physical constants in MKS and a number of usefull units transforms
+
+The MKS object is a table of physical constants
+"""
+
+class __physical_parameters_mks(object) :
+ @property
+ def table(self) :
+ return self._table
+ @property
+ def source(self) :
+ return "https://pdg.lbl.gov/2023/reviews/contents_sports.html"
+ def __init__(self) :
+ """ from https://pdg.lbl.gov/2023/reviews/contents_sports.html """
+ from io import StringIO
+ import pandas
+ import numpy as np
+ # the table
+ self._table=pandas.read_csv(StringIO("""
+definition , latex_macro, latex_name, symbol, value , units , comment
+speed of light in vacuum , c, speedL, c, 299792458. , m/s ,
+Planck constant , h, PConst, h, 6.62607015e-34 , J s , also J/Hz
+reduced Planck constant , hcut, hbar, hbar, 1.0544571817e-34 , J s , also J/Hz is h/2pi
+Avogadro Number , N_{\\mathrm{avo}}, Navo, Navo, 6.02214076e23 , 1/mol ,
+Boltzman constant , k_{\\mathrm{B}}, kB, kB, 1.380649e-23 , J/K ,
+Universal gas constant , R_{*}, Rgas, Rgas, 8.31446261815324 , J/K/mol , defined as kB*Navo
+molar_volume , V_{\\mathrm{mol}}, MolVol, Vmol, 22.41396954e-3 , m3/mol , kB(273.15 K)/(101 325 Pa)
+standard atmosphere pressure , p_{\\mathrm{atm}}, patm, patm, 101325. , pa ,
+zero Celsius , T_{0^{\\circ}\\mathrm{C}}, TzCel, T0C, 273.15 , K ,
+ev in joule , \\mathrm{J}/\\mathrm{ev}, Jev, J_ev, 1.6021766339999e-19 , J/ev ,
+rad2sed , \\mathrm{rad}/\\mathrm{sed}, radTosed, rad2sed, 4.191690043903363e-08, rad s/m , 2*pi/c
+Stefan-Boltzman Constant , \\sigma, sigmaSB, sigmaSB, 5.670374419e-8 , W/m2/K4 ,
+photons SB constant , \\sigma_{\\mathrm{phot}},sigmaSBphot, sigmaSBphot, 2.5247846571310243e-3, micro moles/m2/s/K3,
+standard solar temperature , T_{\\odot}, Tsun, Tsun, 5772. , K ,
+standard solar radius , R_{\\odot}, Rsun, Rsun, 696340e3 , m ,
+standard AU , \mathrm{AU}, AU, AU, 149597870700. , m , exact
+gravitational constant , G_{\\mathrm{N}}, GN, GN, 6.67430e-11 , m3/Kg/s2,
+standard gravitationa acceleration, g_{\\mathrm{N}}, gN, gN, 9.80665 , m/s2 ,
+parsec , \\mathrm{pc}, pc, pc, 3.08567758149e16 , m , exact
+"""),sep='\s*,\s*',comment='#',engine="python",index_col=None)
+ #
+ self._table['comment'] =np.array(['' if str(k).lower() in ['nan'] else k for k in self._table['comment'].values])
+ self._table['units'] =np.array(['' if str(k).lower() in ['nan'] else k for k in self._table['units'].values])
+ #
+ for ik in range(len(self._table)) :
+ line=self._table.iloc[ik]
+ self.__dict__[line.symbol]=line.value
+ def keys(self) :
+ return self._table['symbol'].values
+ def __len__(self) :
+ return len(self._table)
+ def __getitem__(self,this) :
+ if type(this) is type('') :
+ try :
+ return self.__dict__[this]
+ except :
+ raise Exception("Symbol %s not found"%str(this),"")
+ else :
+ try :
+ return self._table.iloc[this]
+ except :
+ raise Exception("Symbol %s not found"%str(this),"")
+ def latex(self,this) :
+ """returns a latex definition for the given constant"""
+ if type(this) is type('') :
+ line=self._table.query('symbol=="'+this+'"')
+ if line is None :
+ raise Exception("Symbol %s not found"%str(this),"")
+ line=line.iloc[0]
+ else :
+ try :
+ line=self._table.iloc[line]
+ except :
+ raise Exception("Symbol %s not found"%str(this),"")
+ out='\\def'+'\\'+line.latex_name+'{'+line.latex_macro+'}'+' % '+line.definition+', '+line.units
+ return out
+ def wl2nu(self,wl) :
+ """wavelength to frequency"""
+ return self.c/wl
+ def nu2wl(self,nu) :
+ """frequency to wavelength"""
+ return self.c/nu
+ def nu2E(self,nu) :
+ """energy to frequency"""
+ return self.h*nu
+ def E2nu(self,E) :
+ """frequency to energy"""
+ return E/self.h
+ def wl2E(self,wl) :
+ """wavelength to energy"""
+ return self.h*self.c/wl
+ def E2wl(self,E) :
+ """energy to wavelength"""
+ return self.c*self.h/E
+ def ev2J(self,ev) :
+ """ ev/J"""
+ return ev*self.J_ev
+ def J2ev(self,J) :
+ """ J/ev"""
+ return J/self.J_ev
+ def radiance2sed(self,radiance) :
+ """ radiance -> spectral_energy_density"""
+ return self.rad2sed*radiance
+ def sed2radiance(self,sed) :
+ """ spectral_energy_density to radiance """
+ return sed/self.rad2sed
+ def nu2bbx(self,nu,T) :
+ """ nu and T to black body x=nu*h/kB*T """
+ return nu*self.h/(T*self.kB)
+ def bbx2nu(self,x,T) :
+ """ black body x: x=nu*h/kB*T, to nu for given T """
+ return x*T*self.kB/self.h
+ def wl2bbx(self,wl,T) :
+ """ wl and T to black body x=c*h/kB*T*wl """
+ return self.c*self.h/(T*self.kB*wl)
+ def bbx2wl(self,x,T) :
+ """ black body x: x=c*h/kB*T*wl, to wl for given T """
+ return self.c*self.h/(T*self.kB*x)
+MKS=__physical_parameters_mks()
+
+def wl2nu(wl) :
+ """wavelength to frequency"""
+ return MKS.c/wl
+def nu2wl(nu) :
+ """frequency to wavelength"""
+ return MKS.c/nu
+def nu2E(nu) :
+ """energy to frequency"""
+ return MKS.h*nu
+def E2nu(E) :
+ """frequency to energy"""
+ return E/MKS.h
+def wl2E(wl) :
+ """wavelength to energy"""
+ return MKS.h*MKS.c/wl
+def E2wl(E) :
+ """energy to wavelength"""
+ return MKS.c*MKS.h/E
+def ev2J(ev) :
+ """ ev/J"""
+ return ev*MKS.J_ev
+def J2ev(J) :
+ """ J/ev"""
+ return J/MKS.J_ev
+def radiance2sed(radiance) :
+ """ radiance -> spectral_energy_density"""
+ return MKS.rad2sed*radiance
+def sed2radiance(sed) :
+ """ spectral_energy_density to radiance """
+ return sed/MKS.rad2sed
+
+def nu2bbx(nu,T) :
+ """ nu and T to black body x=nu*h/kB*T """
+ return nu*MKS.h/(T*MKS.kB)
+
+def bbx2nu(x,T) :
+ """ black body x: x=nu*h/kB*T, to nu for given T """
+ return x*T*MKS.kB/MKS.h
+
+def wl2bbx(wl,T) :
+ """ wl and T to black body x=c*h/kB*T*wl """
+ return MKS.c*MKS.h/(T*MKS.kB*wl)
+
+def bbx2wl(x,T) :
+ """ black body x: x=c*h/kB*T*wl, to wl for given T """
+ return MKS.c*MKS.h/(T*MKS.kB*x)