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personal:portfolio:portopt [2014/05/28 14:53]
antonello
personal:portfolio:portopt [2018/06/18 15:11] (current)
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 In portfolio theory agents attempts to maximise portfolio expected return for a given amount of portfolio risk, or equivalently to minimise risk for a given level of expected return. In portfolio theory agents attempts to maximise portfolio expected return for a given amount of portfolio risk, or equivalently to minimise risk for a given level of expected return.
  
-{{ :​personal:​portfolio:​portfolio_graph.png?nolink |Theoretical framework}}+{{ :​personal:​portfolio:​portfolio_model.png?nolink |Theoretical framework}}
  
 The portfolio management can be portrayed graphically as in the above Figure, where the feasible set of variance-profitability combinations in enclosed by the blue curve and the B-D segment represents the efficient frontier, where no variance can be lowered at productivity'​s price or equivalently no productivity can be increased at price of increasing variance. The portfolio management can be portrayed graphically as in the above Figure, where the feasible set of variance-profitability combinations in enclosed by the blue curve and the B-D segment represents the efficient frontier, where no variance can be lowered at productivity'​s price or equivalently no productivity can be increased at price of increasing variance.
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 \end{equation} \end{equation}
  
-where $x_i$ is the share of the asset $i$, $p_i$ is its productivity and hence $\sum_i {x_i p_i}$ is the overall portfolio productivity and $\sum_i { \sum_j { x_i x_j \sigma_{i,​j}}}$ its variance.+where $x_i$ is the share of the asset $i$, $p_i$ is its productivity, $\sigma_{i,​j}$ is the covariance between assets $i$ and $j$ and hence $\sum_i {x_i p_i}$ is the overall portfolio productivity and $\sum_i { \sum_j { x_i x_j \sigma_{i,​j}}}$ ​is its variance.
  
 As the only quadratic term arises when $i=j$ and $\sigma_{i,​j}$ being the variance is always positive, the problem is convex and hence easily numerically solved. As the only quadratic term arises when $i=j$ and $\sigma_{i,​j}$ being the variance is always positive, the problem is convex and hence easily numerically solved.
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   g++ -std=c++0x -O -shared -Wl,​-soname,​_portopt.so -o _portopt.so QuadProg++.o Array.o anyoption.o portopt.o portopt_wrap.o   g++ -std=c++0x -O -shared -Wl,​-soname,​_portopt.so -o _portopt.so QuadProg++.o Array.o anyoption.o portopt.o portopt_wrap.o
 (then please refer to the python example for usage) ​ (then please refer to the python example for usage) ​
 +
 +If you want to change the output library name (e.g. you want to create _portopt_p3.so for python3 alongside _portopt.so for python2), do it in the %module variable of portopt.i and in the -soname and -o options of the linking command (and don't forget to use the right python included directory in the compilation command).\\
 +You can then load the correct module in your script with something like:
 +  import sys
 +  if sys.version_info < (3, 0):
 +    import portopt
 +  else:
 +    import portopt_p3 as portopt
  
 ===== Usage ===== ===== Usage =====
 +
 +:!: Please notice that the API changed from version 1.1, with the introduction of the ''​port_opt_mean''​ and ''​port_opt_var''​ parameters (both by reference). For the old 1.1 call instructions see [[https://​lobianco.org/​antonello/​personal:​portfolio:​portopt?​rev=1441891152|here]].
 +
 +
 == Linux == == Linux ==
   ./portopt [options]   ./portopt [options]
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 Call: Call:
-  double solveport (const vector< vector <​double>​ > &VAR, const vector<​double>​ &MEANS, const double &alpha, vector<​double>​ &x_h, int &​errorcode)+  double solveport (const vector< vector <​double>​ > &VAR, const vector<​double>​ &MEANS, const double &alpha, vector<​double>​ &x_h, int &​errorcode, string &​errormessage,​ double &​port_opt_mean,​ double &​port_opt_var,​ const double tollerance = 0.000001)
   ​   ​
-== As a lib ising Python: ==+== As a lib using Python: ==
   import portopt   import portopt
-  results = portopt.solveport(var,​means,​alpha)+  results = portopt.solveport(var,​means,​alpha,tolerance# tolerance is optional, default to 0.000001 
 +  functioncost = results[0] 
 +  shares ​      = results[1] 
 +  errorcode ​   = results[2] 
 +  errormessage = results[3] 
 +  opt_mean ​    = results[4] 
 +  opt_var ​     = results[5]
  
 === Options === === Options ===
 <​code>​ <​code>​
-  -h  --help ​                                   Prints this help +  -h  --help ​                                  ​Prints this help 
   -v  --var-file [input_var_file_name] ​        Input file containing the variance/​covariance matrix (relative path)      -v  --var-file [input_var_file_name] ​        Input file containing the variance/​covariance matrix (relative path)   
   -m  --means-file [input_means_file_name] ​    Input file containing the means vector (relative path)  ​   -m  --means-file [input_means_file_name] ​    Input file containing the means vector (relative path)  ​
   -a  --alpha [alpha_coefficient] ​             Coefficient between production and risk in the linear indifference curves ​     -a  --alpha [alpha_coefficient] ​             Coefficient between production and risk in the linear indifference curves ​  
   -f  --field-delimiter [field_delimiter] ​     Character to use as field delimiter (default: ';'​)  ​   -f  --field-delimiter [field_delimiter] ​     Character to use as field delimiter (default: ';'​)  ​
-  -s  --decimal-separator [decimal-separator] ​ Character to use as decimal delimiter (default: '​.'​)'' ​ +  -s  --decimal-separator [decimal-separator] ​ Character to use as decimal delimiter (default: '​.'​) 
 +  -t  --tollerance [tolerance] ​                A tolerance level to distinguish from zero (default: 0.000001) ​
 </​code>​ </​code>​
  
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   * Higher the alpha, lower the agent risk aversion;   * Higher the alpha, lower the agent risk aversion;
   * Set a negative alpha to retrieve the portfolio with the lowest possible variance;   * Set a negative alpha to retrieve the portfolio with the lowest possible variance;
-  * Set alpha to zero to retrieve the portfolio with the highest mean, indipendently ​from variance (solution not guaranteed to be unique); +  * Set alpha to zero to retrieve the portfolio with the highest mean, independently ​from variance (solution not guaranteed to be unique); 
-  * Assets shares are returned in the x_h vector, eventual error code (0: all fine, 1: input data error, 2: problem has no solutions, 3: internal ​solver error) in the errorcode parameter. ​+  * Assets shares are returned in the x_h vector, eventual error code (0: all fine, 1: input data error, 2: no solutions, 3: didn't solve, 4: solver ​internal ​error) in the errorcode parameter. ​ 
 +  * Use option "​tollerance"​ with two l up to version 1.1 included
   ​   ​
   ​   ​
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 You should have received a copy of the GNU Lesser General Public License along with PortOpt. ​ If not, see [[http://​www.gnu.org/​licenses]]. You should have received a copy of the GNU Lesser General Public License along with PortOpt. ​ If not, see [[http://​www.gnu.org/​licenses]].
  
 +
 +===== Citations =====
 +If you use this program or a derivative of it in an academic framework, please cite it!\\
 +Please cite as:
 +  * A. Dragicevic, A. Lobianco, ​ A. Leblois (2016), "​[[http://​dx.doi.org/​10.1016/​j.forpol.2015.12.010|Forest planning and productivity-risk trade-off through the Markowitz mean-variance model]]",​ Forest Policy and Economics, Volume 64, March 2016, Pages 25–34.
  
 ===== Acknowledgements ===== ===== Acknowledgements =====
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 This work was supported by: This work was supported by:
  
-  * a grant overseen by Office National des Forêts through the Forêts pour Demain International Teaching and Research Chair; +  * a grant overseen by Office National des Forêts through the [[http://​www.foretspourdemain.fr |Forêts pour Demain International Teaching and Research Chair]]
-  * the French National Research Agency through the Laboratory of Excellence ARBRE, a part of the "​Investissements d'​Avenir"​ Program (ANR 11 -- LABX-0002-01).+  * the French National Research Agency through the [[http://​mycor.nancy.inra.fr/​ARBRE/​ |Laboratory of Excellence ARBRE]], a part of the "​Investissements d'​Avenir"​ Program (ANR 11 -- LABX-0002-01).
  
  
personal/portfolio/portopt.1401281591.txt.gz · Last modified: 2018/06/18 15:10 (external edit)
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