43 lines
1.1 KiB
Matlab
43 lines
1.1 KiB
Matlab
function dxp=getPowerDeriv(x,p,k)
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%function dxp=getPowerDeriv(x,p,k)
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% The k-th derivative of x^p
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%
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% INPUTS
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% x: base
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% p: power
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% k: derivative order
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%
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% OUTPUTS
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% dxp: k-th derivative of x^p
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%
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% SPECIAL REQUIREMENTS
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% none
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% Copyright © 2011-2012 Dynare Team
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%
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% This file is part of Dynare.
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%
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% Dynare is free software: you can redistribute it and/or modify
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% it under the terms of the GNU General Public License as published by
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% the Free Software Foundation, either version 3 of the License, or
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% (at your option) any later version.
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%
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% Dynare is distributed in the hope that it will be useful,
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% but WITHOUT ANY WARRANTY; without even the implied warranty of
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% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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% GNU General Public License for more details.
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%
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% You should have received a copy of the GNU General Public License
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% along with Dynare. If not, see <https://www.gnu.org/licenses/>.
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if (abs(x) < 1e-12) && (p > 0) && (k > p) && (abs(p - round(p)) < 1e-12)
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dxp = 0;
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else
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dxp = x^(p-k);
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for i=0:k-1
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dxp = dxp*p;
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p = p-1;
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end
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end
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end
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