f[x_,y_]:=x*y*Log[y]

solPresne=DSolve[{a'[t]==t*a[t]*Log[a[t]],a[0]==3},a[t],t]

h=0.01;
x0=0;
y0=3;
koniec=1;

Numries[x_,y_,f_,h_]:=y+h*f[x,y]

Pres[x_]:=(3^(E^((x^2)/2)))

x[0]=x0;
y[0]=y0;
n=koniec/h;

Do[{x[i]=x0+i*h,y[i]=Numries[x[i-1],y[i-1],f,h]},{i,1,n,1}]
data=Table[{x[i],y[i]},{i,0,n}];
data1=Table[Abs[(y[i]-Pres[x[i]])],{i,0,n}];
vysledky=Table[{x[i],y[i],Pres[x[i]], Abs[(y[i]-Pres[x[i]])]},{i,0,n}];
maxerror=Max[data1];

PaddedForm[TableForm[vysledky],{12,4}]

g=Plot[Pres[x],{x,0,1},PlotStyle->{RGBColor[1,0,0],PlotRange->{{0,1},{0,10}},Thickness[0.005]}]

graf1=ListPlot[data,PlotStyle->{RGBColor[0,0,1]}]

Show[g,graf1]

(*zadanie matie A*)
a11=-0.1;a12=1.0;a21=-1.0;a22=-0.1;
A={{a11,a12},{a21,a22}}
MatrixForm[A]

(*definicia pravej strany*)

f1[x_,y1_,y2_]:=a11*y1+a12*y2
f2[x_,y1_,y2_]:=a21*y1+a22*y2