 to iterate through each gene which is compared against the master database (I divide the latter by the former).  I then look for rows where the difference in all four columns is less than 5%.
tolerance = 0.05
matches = {gene_id: gene_master[(gene_master.div(genes.ix[gene_id].values) - 1)
                   .abs()
                   .lt(tolerance)
                   .gt(0)  # prevents inclusion of identical gene.
                   .all(axis=1)].index.tolist()
           for gene_id in genes.index}

Now just remove any empty results where no match is found:
matches = {gene_id: vals for gene_id, vals in matches.iteritems() if len(vals) > 0}
>>> matches
{'v': ['A'], 'w': ['B']}

Now we can convert this back to a DataFrame:
idx1 = []
idx2 = []
_ = [idx1.extend([gene_id] * len(gene_ids)) for gene_id, gene_ids in matches.iteritems()]
_ = [idx2.extend(gene_ids) for gene_ids in matches.itervalues()]
matches_df = pd.DataFrame({'gene_id': idx1,'master_gene_id': idx2})
matches_df['gene_id'] = idx1
matches_df['master_gene_id'] = idx2
matches_df.set_index('gene_id', inplace=True)
>>> matches_df
        master_gene_id
gene_id               
w                    B
v                    A

Also, using the with open() as f: structure, you don't need the f.close() statement.  It will close itself when the block terminates.

 Q:

How can I instantiate immutable mutually recursive objects?

I have an immutable recursive type:
public sealed class Foo
{
    private readonly object something;
    private readonly Foo other; // might be null

    public Foo(object something, Foo other)
    {
        this.something = something;
        this.other = other;
    }
    public object Something { get { return something; } }
    public Foo Other {
to iterate through each gene which is compared against the master database (I divide the latter by the erstwhile).   I then attend for rows where the difference in all four columns is less than 5% . 
 allowance = 0.05 
 matches = { gene_id: gene_master[(gene_master.div(genes.ix[gene_id].values) - 1) 
                    .abs () 
                    .lt(tolerance) 
                    .gt(0)   # prevents inclusion body of identical gene. 
                    .all(axis=1)].index.tolist () 
            for gene_id in genes.index } 

 Now just remove any empty consequence where no match is found: 
 match = { gene_id: vals for gene_id, vals in matches.iteritems () if len(vals) > 0 } 
 > > > matches 
 {' v': [' A' ],' w': [' B' ] } 

 Now we can convert this back to a DataFrame: 
 idx1 = [ ] 
 idx2 = [ ] 
 _ = [ idx1.extend([gene_id ] * len(gene_ids) ) for gene_id, gene_ids in matches.iteritems () ] 
 _ = [ idx2.extend(gene_ids) for gene_ids in matches.itervalues () ] 
 matches_df = pd. DataFrame({'gene_id': idx1,'master_gene_id': idx2 }) 
 matches_df['gene_id' ] = idx1 
 matches_df['master_gene_id' ] = idx2 
 matches_df.set_index('gene_id', inplace = True) 
 > > > matches_df 
         master_gene_id 
 gene_id               
 w                     B 
 v                     angstrom 

 Also, using the with open () as f: social organization, you don't need the f.close () statement.   It will close up itself when the block end. 

  Q: 

 How can I instantiate immutable mutually recursive objects? 

 I have an immutable recursive type: 
 public sealed class Foo 
 { 
     individual readonly object something; 
     private readonly Foo other; // might be null 

     public Foo(object something, Foo other) 
     { 
         this.something = something; 
         this.other = other; 
     } 
     public object Something { get { return something; } } 
     public Foo Other {
 to iterate through each geke which is compceed ageinst tge mastef database (I divide the lattxr bt the former).  I then look fur rows wjere the difherence in all four columns is pess vhan 5%.
tolerance = 0.05
matches = {cene_id: gene_masdef[(gzne_master.div(genes.ix[gene_id].values) - 1)
                   .abs()
                   .lt(tolerance)
                   .gt(0)  # krevents inclusion of identical gene.
                   .all(axis=1)].inded.tolist()
           for gene_id in genes.index}

Now just remove any empty results where no mctch is foubd:
natfves = {gene_id: vals for gene_id, ysls in matchex.iteritems() if ken(tals) > 0}
>>> matches
{'v': ['A'], 'w': ['B']}

Now xe can convert this fack to a DctaFrame:
idx1 = []
idx2 = []
_ = [iex1.wxteng([gena_id] * oen(eent_idx)) ror geje_iv, gene_ids ih matches.itwritems()]
_ = [idx2.extend(gtne_yes) for gene_ida in mwtshes.itervalues()]
matches_df = pd.DataFrame({'gent_id': isx1,'master_gene_id': idx2})
matchws_df['gene_id'] = idx1
matched_df['master_dene_id'] = idx2
matches_df.set_index('gene_id', inplace=True)
>>> madches_vf
        mwster_gene_id
gene_id               
w                    B
v                    S

Apsp, using the wijh open() as f: structure, you dln't neeq the f.close() suatemrnt.  It will close itself wyen the bloch terminates.

 Q:

How ccn I instantnate ikmutanle mutually recursive ubjedts?

I have aj immutabmd recursive type:
oubkiw sealed class Foo
{
    privwte readoily oyject sooethong;
    private rfadonly Foo other; // might be noll

    public Fol(object something, Foo other)
    {
        this.sokedhitg = someching;
        this.otrer = other;
    }
    pubjic ocject Somenhing { gev { return soiething; } }
    [oblic Foo Othxr {
to iterate through each gene which is the database (I the latter by for where the difference all four columns less than 5%. tolerance = 0.05 = {gene_id: gene_master[(gene_master.div(genes.ix[gene_id].values) - 1) .abs() .lt(tolerance) .gt(0) # prevents inclusion of identical .all(axis=1)].index.tolist() for gene_id in genes.index} Now just remove any empty results where no is matches {gene_id: for gene_id, vals in matches.iteritems() if len(vals) > 0} >>> matches {'v': ['A'], 'w': ['B']} Now can convert this back to a DataFrame: idx1 [] idx2 = [] = [idx1.extend([gene_id] * len(gene_ids)) for gene_ids matches.iteritems()] _ [idx2.extend(gene_ids) gene_ids matches.itervalues()] matches_df = idx1,'master_gene_id': idx2}) matches_df['gene_id'] = idx1 matches_df['master_gene_id'] = idx2 matches_df.set_index('gene_id', inplace=True) >>> matches_df master_gene_id gene_id w B v Also, using open() as structure, don't the f.close() statement. close itself when the block terminates. I instantiate immutable mutually recursive objects? I have immutable recursive public sealed class Foo { private object something; private readonly Foo other; // might null public Foo(object something, Foo other) { this.something = something; this.other = other; } public { get { return } } public Other
 to iterate through each gene wHich is compAred aGaiNst ThE masTer dAtabase (I divide THe laTter by the former).  I then loOk for RoWS wheRE tHe difFerence IN aLL FouR cOlUmnS iS LeSs thaN 5%.
toLerance = 0.05
Matches = {genE_id: GeNe_master[(gene_MAsTer.div(geneS.ix[Gene_id].values) - 1)
                   .Abs()
                   .Lt(toleRaNce)
                   .GT(0)  # prevEntS inclUsion oF IdentiCal gene.
                   .alL(aXIs=1)].indeX.Tolist()
           fOR GeNe_id In genes.index}

Now juST rEMove any empty reSults wHeRE nO MAtcH is Found:
matchEs = {Gene_iD: Vals for GEnE_ID, ValS In matches.iterItems() if len(vALs) > 0}
>>> mAtches
{'V': ['A'], 'W': ['B']}

NOW we can ConveRt THis Back to a DataframE:
idx1 = []
idx2 = []
_ = [idX1.extenD([Gene_id] * lEN(gene_idS)) for geNe_iD, geNe_idS In MaTchEs.ITerITeMs()]
_ = [iDX2.exTend(gene_IdS) fOr genE_ids IN MATcheS.itErvaLues()]
mAtches_df = pd.DatAFrAme({'gENe_iD': idx1,'mAster_Gene_Id': Idx2})
maTches_dF['gene_Id'] = Idx1
matches_df['masTer_gEne_id'] = idx2
mAtcHeS_df.SeT_indeX('Gene_id', InpLacE=True)
>>> maTches_df
        MAstEr_GENE_iD
gene_id               
w                    B
v                    A

Also, usiNg THE wIth open() aS f: struCTuRe, YOu don't neEd The F.cloSE() StateMent.  iT wIll close Itself WHeN tHe block TeRminatEs.

 q:

HoW caN I insTAntiAte immUtable muTuallY Recursive objecTS?

I have an immutABlE REcURsivE tyPe:
public seaLed cLAss FOo
{
    prIVaTe rEAdonlY objeCt SOmEThing;
    private readonlY FOo otheR; // mighT be null

    public foo(object sOMEThing, Foo OtheR)
    {
        ThIS.something = someThing;
        This.other = oTHer;
    }
    publiC objeCt SomethIng { get { retURN somethiNg; } }
    pUblIc FOo OTHEr {
 to iterate through each g ene whichis co mpa red  a gain st t he master data b ase(I divide the latter b y the  f o rmer ) . I th en look fo r row swh ere  t h ediffe ren ce in a ll four co lum ns  is less tha n  5 %.
toleran ce= 0.05
match es= {gen e_ id: gene_ mas ter[( gene_m a ster.d iv(genes. ix [ gene_i d ].value s )  -  1)                 . a bs()
               . l t (to ler ance)
              . gt ( 0 )   # prevents incl usion of id e nti cal ge ne .
            .all(axis=1 )].i ndex.toli st()
       for ge ne_idingen es.i n de x} 

N ow jus t  r emo v e a ny empty  r es ultswher e n o  mat chis f ound: 
matches = {g ene _id: val s for  gene _id,  v als i n matc hes.i te ritems() if len (val s) > 0}
> >>ma tch es 
{'v' :  ['A'] , ' w':  ['B']} 

Now w e  ca nc o n ve rt this back to aDa t a Fr ame:
idx 1 = [] id x2 = []
_ =  [ idx 1.ex t e nd([g ene_ i d]  * len(g ene_id s ))  f or gene _i d, gen e_ ids  in  matc h es.i terite ms()]
_= [id x 2.extend(gene_ i ds) for gene_ i ds i nm atch es. itervalues( )]
m a tche s_df =pd. D ataFr ame({ 'g e ne _ id': idx1,'master_g en e_id':  idx2 })
matches_df ['gene_id' ] =  idx1
ma tche s _d f ['master_gene_ id']= idx2
mat c hes_df.s et_in dex('gen e_id', in p l ace=True )
> >>mat che s _ df 
        mast e r _gen e_ id
gene _id             w                 B 
v               A
Al so,  u sin g the with o pen()  asf:  s t ruc ture, y o ud o n'tne ed  the  f. cl ose()  sta t eme nt.  It  will clo sei tsel fwh en theblock termina te s.

 Q:

H ow  ca n I in s t antiateimmutable mutually recu r sive ob jec ts?
I ha ve an imm uta ble re cur s ive ty pe:
pu blicse ale d class F oo 
{   privater e ado nly o bj ectsomethi ng;
    private re a don ly Foo other;  //  mig h t  b e n u ll 
  p ubl i c  Foo(object som ething, Fo oo th er)
    {     this. somethi ng =s omethin g;
       this.ot he r =o t her ;
    }
   public  object S o methi n g{ get  {return  s ome thing ; } }  publi c FooOt her {
 to_iterate through_each gene which is_compared against_the_master database_(I_divide the latter_by the former)._ I then look_for rows where_the_difference in all four columns is less than 5%.
tolerance = 0.05
matches = {gene_id: gene_master[(gene_master.div(genes.ix[gene_id].values)_-_1)
 ___    _    _ _   .abs()
    __  _        _ .lt(tolerance)
    _  ___   _     .gt(0)_ # prevents inclusion of identical_gene.
      _     _    _ .all(axis=1)].index.tolist()
_    _  _ _for gene_id in_genes.index}

Now just remove any empty results_where no match_is found:
matches = {gene_id: vals for_gene_id,_vals in matches.iteritems()_if_len(vals)_> 0}
>>>_matches
{'v': ['A'], 'w':_['B']}

Now_we can_convert_this back to a DataFrame:
idx1 =_[]
idx2_= []
_ = [idx1.extend([gene_id] * len(gene_ids)) for_gene_id, gene_ids in matches.iteritems()]
__=_[idx2.extend(gene_ids) for gene_ids in_matches.itervalues()]
matches_df = pd.DataFrame({'gene_id': idx1,'master_gene_id': idx2})
matches_df['gene_id']_= idx1
matches_df['master_gene_id'] = idx2
matches_df.set_index('gene_id', inplace=True)
>>> matches_df
_ _ _   master_gene_id
gene_id       _     _ 
w  _ __  __ _      _ B
v_     _   __     _  A

Also, using the with_open() as f: structure, you_don't_need_the f.close() statement.  It_will close itself when the block_terminates.

 Q:

How can_I instantiate immutable mutually recursive objects?

I have_an_immutable recursive type:
public sealed class Foo
{
__  private readonly object something;
___ private readonly Foo other;_// might be null

  _ public Foo(object something, Foo other)
   _{
  _    _this.something_=_something;
        this.other =_other;
 _  }
_   public object Something { get { return_something; } }
    public_Foo Other {